See the picture I sent you before or do a search online for 3100 1957 head light switch wiring you will will find all kinds of diagrams out there.
your comment below
"I have seen diagrams that show a ground wire attaches to the terminal on the opposite side of the switch from the 3 contact terminal"
those are not ground wires but circuit wires (yes the ground side of the circuit) but not direct to ground.
You should have one of your wires on those posts. (wire attaches to the terminal on the opposite side of the switch from the 3 contact terminal) side
The other in the middle for the switch.
